Anti-flare semiconductor packages and related methods

ABSTRACT

Implementations of semiconductor packages may include: a semiconductor die having a first side and a second side. A first side of an optically transmissive lid may be coupled to the second side of the semiconductor die through one or more dams. The packages may also include a light block material around the semiconductor package extending from the first side of the semiconductor die to a second side of the optically transmissive lid. The package may include an opening in the light block material on the second side of the optically transmissive lid that substantially corresponds with an active area of the semiconductor die.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of the earlier U.S.Utility Patent Application to Shou-Chian Hsu entitled “Anti-FlareSemiconductor Packages and Related Methods,” application Ser. No.16/456,917, filed Jun. 28, 2019, now pending, the disclosure of which ishereby incorporated entirely herein by reference.

BACKGROUND 1. Technical Field

Aspects of this document relate generally to semiconductor packages,such as complementary metal oxide semiconductor (CMOS) image sensor chipscale packages (CISCSPs) for consumer electronic devices such ascameras, phones, tablets, and laptops. More specific implementationsinvolve image sensor packages having lids.

2. Background

Complementary metal-oxide-semiconductor (CMOS) image sensor chip scalepackages (CISCSP) have a broad range of applications due to theirsmall/thin form and low overall cost. Current CISCSPs include atransparent glass covering the entire chip.

SUMMARY

Implementations of semiconductor packages may include: a semiconductordie having a first side and a second side. A first side of an opticallytransmissive lid may be coupled to the second side of the semiconductordie through one or more dams. The packages may also include a lightblock material around the semiconductor package extending from the firstside of the semiconductor die to a second side of the opticallytransmissive lid. The package may include an opening in the light blockmaterial on the second side of the optically transmissive lid thatsubstantially corresponds with an active area of the semiconductor die.

Implementations of semiconductor packages may include one, all, or anyof the following:

The second side of the optically transmissive lid may include anindentation on each of a first edge and a second edge of the opticallytransmissive lid.

The light block material may be a molding compound.

The semiconductor package may include a redistribution layer coupled tothe first side of the semiconductor die.

The opening may correspond with a pixel array in the semiconductor die.

The semiconductor package may further include one or more die padscoupled to each of the one or more dams.

The semiconductor package may further include one or more die padscoupled to each of the one or more dams.

The semiconductor package may further include a plurality of throughsilicon vias (TSVs), a passivation layer, a solder mask, and two or moresolder bumps.

Implementations of semiconductor packages may include: a semiconductordie having a first side and a second side and a first side of anoptically transmissive lid coupled to the second side of thesemiconductor die through one or more dams. A second side of theoptically transmissive lid may include a first recess and a secondrecess on a first edge and a second edge of the optically transmissivelid, respectively. The package may also include a light blockingmaterial encapsulating the semiconductor package from a first side ofthe semiconductor die into the first recess and into the second recesson the second side of the optically transmissive lid.

Implementations of semiconductor packages may include one, all, or anyof the following:

The semiconductor package may further include an opening in the lightblocking material. The opening may be between the first recess and thesecond recess on the second side of the optically transmissive lid.

The light block material may be a molding compound.

The semiconductor package may further include a redistribution layer(RDL) coupled to a first side of the semiconductor die.

An active area of the semiconductor die may correspond with the firstrecess and the second recess in the optically transmissive glass lid.

The semiconductor package may further include one or more die padscoupled to each of the one or more dams.

The semiconductor package may further include a plurality of throughsilicon vias (TSVs), a passivation layer, a solder mask, and two or moresolder bumps.

Implementations of semiconductor packages may be formed usingimplementations of methods for forming semiconductor package, themethods may include: providing an optically transmissive lid having afirst side and a second side. The optically transmissive lid may includea plurality of recesses on the second side of the optically transmissivelid. The method may also include coupling a semiconductor wafer to thefirst side of the optically transmissive lid. The semiconductor wafermay include a first side and a second side. The second side of the wafermay include a plurality of active areas. The method may also includesingulating the semiconductor wafer and the optically transmissive lidbetween each of the plurality of active areas in the wafer to form aplurality of semiconductor packages. The method may include coupling thesecond side of the optically transmissive lids of each of thesemiconductor packages to a carrier wafer. The recesses on the opticallytransmissive lid may form a space between the carrier wafer and theoptically transmissive lids. The method may include applying lightblocking material to each of the semiconductor packages. The lightblocking material may encapsulate each of the semiconductor packagesfrom a first side of the package into and including the recesses on theoptically transmissive lid. The method may include singulating throughthe light blocking material to form a plurality of encapsulatedsemiconductor packages. The recesses may be on a first edge and a secondedge of each of the optically transmissive lids around an opening in thelight blocking material.

Implementations of methods of forming semiconductor packages may includeone, all, or any of the following:

The method may include forming the plurality of recesses on the secondside of the optically transmissive lid through one of etching or laserablation.

The light blocking material may include a molding compound.

The method may further include forming a plurality of through siliconvias (TSVs), a passivation layer, a redistribution layer, a solder mask,and coupling solder bumps to each of the semiconductor packages.

An opening in the light blocking material on each of the pluralitysemiconductor packages may correspond with an active area in thesemiconductor die.

The method may further include coupling dam material to the opticallytransmissive lid.

The foregoing and other aspects, features, and advantages will beapparent to those artisans of ordinary skill in the art from theDESCRIPTION and DRAWINGS, and from the CLAIMS.

BRIEF DESCRIPTION OF THE DRAWINGS

Implementations will hereinafter be described in conjunction with theappended drawings, where like designations denote like elements, and:

FIG. 1 is a cross sectional view of an implementation of a semiconductorpackage;

FIG. 2 is a top view of an implementation of a semiconductor package;

FIG. 3 is a side view of an implementation of an optically transmissivelid;

FIG. 4 is a side view of an implementation of an implementation of asemiconductor wafer coupled with an implementation of an opticallytransmissive lid;

FIG. 5 is side view of a panel of an implementation of a semiconductorpackages after various processing steps;

FIG. 6 is a cross sectional view of a semiconductor package aftersingulation;

FIG. 7 is a cross sectional view of an implementation of twosemiconductor packages coupled with an implementation of a carrierwafer;

FIG. 8 is a cross sectional view of an implementation of twosemiconductor packages after encapsulation with an implementation of alight blocking material;

FIG. 9 is a cross sectional view of an implementation of a semiconductorpackage after singulation; and

FIG. 10 is a top view of an implementation of a top of a semiconductorpackage as described herein.

DESCRIPTION

This disclosure, its aspects and implementations, are not limited to thespecific components, assembly procedures or method elements disclosedherein. Many additional components, assembly procedures and/or methodelements known in the art consistent with the intended semiconductorpackages will become apparent for use with particular implementationsfrom this disclosure. Accordingly, for example, although particularimplementations are disclosed, such implementations and implementingcomponents may comprise any shape, size, style, type, model, version,measurement, concentration, material, quantity, method element, step,and/or the like as is known in the art for such semiconductor packages,and implementing components and methods, consistent with the intendedoperation and methods.

In various image sensor implementations, a transparent or translucentmaterial is employed to cover the area of the image sensor die that isexposed to light. The transparent or translucent material of the coveror lid can allow light to enter package outside the sensor area whichcan result in flare being observed in the output from the image sensor.Referring to FIG. 1, an implementation of a semiconductor package 2 isillustrated. The semiconductor package includes a semiconductor die 4coupled with an optically transmissive lid 6. The second side of thesemiconductor die 4 is coupled to the first side of the opticallytransmissive lid 6. In various implementations, the opticallytransmissive lid 6 may include, by non-limiting example, glass,polycarbonate, acrylic, plastics, or other materials that allow some orall of a desired wavelength of light to pass through the material. Invarious implementations, the optically transmissive lid may be coupledto the semiconductor die through an adhesive material. In variousimplementations, the adhesive may include, by non-limiting example,epoxy, resin, polymers, glue, solders, and other adhesive materials usedin coupling components of semiconductor devices. In someimplementations, the adhesive may include silver or other metal fillersto create electrical conductivity for the adhesive. In someimplementations, a dam 8 is coupled between the optically transmissivelid 6 and the semiconductor die 4. The dam may create a gap between thelid and the active area of the semiconductor die. In variousimplementations, the dam material may include, by non-limiting example,liquid epoxy, silicone, or other encapsulants that provide deviceprotection, reduce warpage, demonstrate excellent flow, offer goodadhesion to multiple substrates and have the strength to handleover-molding and subsequent process steps.

Still referring to FIG. 1, the semiconductor package 2 also includes twothrough silicon vias (TSVs) 10 extending from a first side of thesemiconductor die to a die pad 11 on the second side of thesemiconductor die 4. Coupled to the first side of the semiconductor die4 is a redistribution layer (RDL) 12 extending from a first edge of thesemiconductor die 4 to a second edge of the semiconductor die 4. A ballgrid array 14 is coupled to the first side of the semiconductor die 4and is surrounded by the RDL 12.

As illustrated, a light blocking material/masking material 16 surroundsthe semiconductor package 2 extending from the first side of thesemiconductor die 4 to a second side of the optically transmissive lid6. The light blocking material 16 does not fully encapsulate thesemiconductor package. As illustrated in FIG. 2, an opening 18 in thelight blocking material 16 exists on the second side of the opticallytransmissive lid 6 that substantially corresponds with the active areaof the semiconductor die (image sensor array). In variousimplementations, the light blocking material may be a molding compound.In other implementations, the light blocking material may include othermaterials that are capable of blocking light at any desired frequencyfrom entering through the sides of the optically transmissive lid suchas epoxies, resins, or polymers.

The light blocking material may be capable of ensuring no light entersthe package from non-sensor areas of the semiconductor package. Blockinglight from entering non-sensor areas may prevent flare. Flare maydegrade the performance of the image sensor. Flare occurs when lightbounces off metal pieces/structures in the semiconductor packages andinto the sensor of the image sensor die. For example, metal structuresmay be exposed in the die streets of a semiconductor die aftersingulation. Without light blocking material around the sides of anoptically transmissive lid, light may enter the lid from many angles andmay reflect off the metal in the die streets. The stray light may enterdirectly on a side of the lid, hit the metal structures, reflect aroundwithin the lid and then hit the sensor of the die. Applying lightblocking material around the edges of the optically transmissive lidresults in a structure where light may only enter the portion of theoptically transmissive lid that corresponds with the sensor or pixels ofthe semiconductor package thereby preventing light from reaching anymetal structures within the semiconductor package. As a result ofeliminating or substantially eliminating reflections from metalstructures within the package, flare and the resulting image degradationcaused by flare also prevented.

As illustrated, the second side of the optically transmissive lid 6 hasindentations 20 on each of a first edge 21 and a second edge 22 of thelid 6. The light blocking material 16 may fill these indentations andthe indentations 20 may prevent the light blocking material 16 fromentering the opening 18. Referring to FIG. 2, a top view of the opening18 surrounded by the light blocking material 16 is illustrated. Theopening 18 may correspond with a pixel array in the semiconductor die.

Referring to FIG. 3, a cross sectional view of an optically transmissivelid 24 is illustrated. The optically transmissive lid 24 includes aplurality of recesses 26 formed on a first side of the lid. In someimplementations, the plurality of recesses may be pre-formed in theoptically transmissive lid. In other implementations, the plurality ofrecesses 26 may be formed through etching or laser ablation incombination with various patterning methods (such as photolithography).In various implementations, the etching may include wet etching or dryetching. Various implementations of methods of manufacturingsemiconductor packages as described herein may be used including waferlevel processes and panel level processes. Panel level processes mayhave cost and productivity advantages. Panel level processing may allowfor parallel processing of more units of semiconductor packages in agiven period compared with wafer level processes. Panel level processingmay also reduce waste that results from processing partial die in awafer level process. A method for forming a semiconductor package mayinclude providing an optically transmissive lid as illustrated in FIG.3. In various implementations, the optically transmissive lid mayinclude, by non-limiting example, glass, polycarbonate, acrylic,plastics, or other materials that allow some or all of a desiredwavelength of light to pass through the material.

The method may further include coupling a semiconductor wafer to a firstside of the optically transmissive lid. The semiconductor wafer mayinclude a plurality of active areas on a second side of the wafer. Invarious implementations, the active areas may include pixel arrays.Referring to FIG. 4, a semiconductor wafer 28 coupled to an opticallytransmissive lid 24 is illustrated. The plurality of active areas 30 areenclosed in a gap 31 between the semiconductor material 28 and theoptically transmissive lid 24. Dams 34 on either side of each of theplurality of active areas 32 helps to form the gaps 31. In variousimplementations, the dams 34 may be coupled to die pads 36 in thesemiconductor wafer 28 on either side of the active areas 30.

Referring to FIG. 5, an implementation of a panel 37 of semiconductorpackages is illustrated. In various implementations, the panel may beprocessed using a standard chip scale package process. For example, themethod may include forming a plurality of through silicon vias (TSVs) 38through the first side of the semiconductor wafer on either side of theactive area 30. The TSVs may be formed through drilling, etching, orother methods of forming a hole through a semiconductor die. The methodmay also include forming a passivation layer and RDL 40 over theplurality of semiconductor die 43. The method may also include forming asolder mask and coupling a plurality of balls 42 to form a ball gridarray (BGA) to the first side of the semiconductor die 43. In variousimplementations, different surface mount interconnects such as, bynon-limiting example, pillars, stud bumps, and any other interconnecttype may be used. In some implementations, the interconnects may beformed of copper, solder, or other electrically conductive materials.

The method may also include singulating the semiconductor wafer and theoptically transmissive lid between each of the plurality of active areasin the wafer to form a plurality of semiconductor packages. The packagesmay be singulated through sawing or dicing. Referring to FIG. 6, animplementation of a semiconductor package 44 after singulation isillustrated. The method also includes coupling each of the semiconductorpackages to a carrier wafer. The second side of the opticallytransmissive lids 48 of each of the semiconductor packages 44 is coupledto the carrier wafer 49 as illustrated in FIG. 7. In variousimplementations, the semiconductor packages may be coupled to thecarrier wafer through a pick and place process. Recesses are located onthe first edge and the second edge of each of the optically transmissivelids. As illustrated, the recesses 26 on the second side of each of theoptically transmissive lids 24 form a space 46 between the carrier wafer49 and the optically transmissive lids 24. The space is then filled withlight blocking material allowing the light blocking material toencapsulate each of the packages and leave an opening on the second sideof the optically transmissive lid. In various implementations, theopening is sized to expose only a sensor area of the semiconductor die.In other implementations, the opening may be sized to substantiallyexpose only a sensor area of the semiconductor die.

Referring to FIG. 8, the plurality of semiconductor packages 44 areillustrated after applying light blocking material 50 to each of thesemiconductor packages. As previously described, the light blockingmaterial 50 encapsulates each of the semiconductor packages from a firstside of the packages into and including the recesses 26 on the opticallytransmissive lids 24. In various implementations, the light blockingmaterial 50 may include a molding compound. In various implementations,the molding compound may include, by non-limiting example, epoxies,resins, polymers, solders, and other materials that may used to seal adie to a lid of a semiconductor package.

The light blocking material may prevent stray light from entering theactive area of the semiconductor die by preventing light from enteringthe semiconductor packages on the sides of the optically transmissivelid. In various implementations, the method also includes singulatingthrough the light blocking material to form a plurality of encapsulatedsemiconductor packages. The semiconductor packages may be singulatedthrough sawing or dicing.

Referring to FIG. 9, an implementation of a semiconductor package 52 isillustrated. The package includes a semiconductor die 53 coupled to anoptically transmissive lid 57. The semiconductor die 53 includes a firstside 54 and a second side 56. The second side 56 of the semiconductordie 53 includes an active area including a pixel array. The second side56 of the die 53 is coupled to the first side 59 of the opticallytransmissive lid 57. In various implementations, the die and the lid maybe coupled through adhesive material. By non-limiting example, theadhesive material may include epoxy, resin, polymers, glue, and otheradhesive materials used in coupling components of semiconductor devices.In other implementations, the die and the lid may be coupled throughdams. The dams may be formed of any of the materials previouslymentioned herein. The dam creates a gap between the semiconductor die 53and the optically transmissive lid 57.

A second side 58 of the optically transmissive lid 57 may include afirst recess 60 and a second recess 62 on a first edge 64 and a secondedge 66 of the optically transmissive lid 57. The semiconductor package52 also includes a light blocking material 68 encapsulating thesemiconductor package from a first side of the semiconductor die intothe first recess 60 and into the second recess 62 on the second side ofthe lid. Referring to FIG. 10, the opening 70 in the light blockingmaterial 68 is sized to expose only, or substantially only, the sensorarea of the semiconductor die. The size of the opening may prevent straylight from entering the sensor area in the active area of thesemiconductor die. In various implementations, the light blockingmaterial may include a molding compound. As previously described, thelight blocking material may include other materials that are capable ofblocking visible light from entering through the sides of the opticallytransmissive lid in other implementations. The light blocking materialmay be capable of ensuring no light enters the package from non-sensorareas of the semiconductor package. Blocking light from enteringnon-sensor areas may prevent flare and enhance image quality.

Referring again to FIG. 9, the semiconductor package also includes aredistribution layer (RDL) 72 coupled to the first side of thesemiconductor die 53. The RDL 72 is coupled to die pads 74 through aplurality of through silicon vias (TSVs) 76. As illustrated, the diepads are located on either side of the active area of the image sensordie. The semiconductor package also includes a passivation layer, asolder mask, and two solder bumps 78 on the first side of thesemiconductor die 53. In some implementations, more than two bumps maybe coupled to a first side of the semiconductor die.

Implementations of semiconductor packages described herein may have highreliability due to protection/molding being present on 6 sides of thesemiconductor package. The light blocking material and related processesmay be used in other implementations of image sensor packages such as,by non-limiting example, charge-coupled devices (CCD), complementarymetal-oxide-semiconductor (CMOS) or N-type metal-oxide-semiconductor(NMOS, Live MOS) packages. It might be advantageous to apply lightblocking material to any semiconductor package including an opticallytransmissive lid to prevent unwanted light from entering the package.

In places where the description above refers to particularimplementations of semiconductor packages and implementing components,sub-components, methods and sub-methods, it should be readily apparentthat a number of modifications may be made without departing from thespirit thereof and that these implementations, implementing components,sub-components, methods and sub-methods may be applied to othersemiconductor packages.

What is claimed is:
 1. A semiconductor package comprising: a semiconductor die comprising a first side and a second side; a first side of an optically transmissive lid coupled to the second side of the semiconductor die through one or more dams; a light block material comprised around the semiconductor package extending from the first side of the semiconductor die to a second side of the optically transmissive lid; and an opening in the light block material on the second side of the optically transmissive lid that substantially corresponds with an active area of the semiconductor die; wherein six outer surfaces of the semiconductor package comprise the light block material.
 2. The semiconductor package of claim 1, wherein the second side of the optically transmissive lid comprises an indentation on each of a first edge and a second edge of the optically transmissive lid.
 3. The semiconductor package of claim 1, wherein the light block material is a molding compound.
 4. The semiconductor package of claim 1, further comprising a redistribution layer coupled to the first side of the semiconductor die.
 5. The semiconductor package of claim 1, wherein the opening corresponds with a pixel array in the semiconductor die.
 6. The semiconductor package of claim 1, further comprising one or more die pads coupled to each of the one or more dams.
 7. The semiconductor package of claim 1, further comprising a plurality of through silicon vias (TSVs), a passivation layer, a solder mask, and two or more bumps.
 8. A semiconductor package comprising: a semiconductor die comprising a first side and a second side; a first side of an optically transmissive lid coupled to the second side of the semiconductor die through one or more dams; and a light block material encapsulating the semiconductor package; wherein the light block material is directly coupled to a second side of the optically transmissive lid opposite the first side of the optically transmissive lid; and wherein the light block material is directly coupled to the semiconductor die.
 9. The semiconductor package of claim 8, further comprising an opening in the light block material, wherein the optically transmissive lid is exposed through the opening.
 10. The semiconductor package of claim 8, wherein the light block material is a molding compound.
 11. The semiconductor package of claim 8, further comprising a redistribution layer (RDL) coupled to the first side of the semiconductor die.
 12. The semiconductor package of claim 8, wherein an active area of the semiconductor die corresponds with a first recess and a second recess in the optically transmissive lid.
 13. The semiconductor package of claim 8, further comprising one or more die pads coupled to each of the one or more dams.
 14. The semiconductor package of claim 8, further comprising a plurality of through silicon vias (TSVs), a passivation layer, a solder mask, and two or more bumps.
 15. A semiconductor package comprising: a semiconductor die comprising a first side and a second side; a first side of an optically transmissive lid coupled to the second side of the semiconductor die through one or more dams; a light block material comprised around the semiconductor package; and an opening in the light block material on the second side of the optically transmissive lid that substantially corresponds with an active area of the semiconductor die; wherein the one or more dams are directly coupled to the first side of the optically transmissive lid and the second side of the semiconductor die; wherein the light block material is directly coupled to the second side of the optically transmissive lid, the second side of the optically transmissive lid opposite the first side of the optically transmissive lid.
 16. The semiconductor package of claim 15, wherein the light block material is a molding compound.
 17. The semiconductor package of claim 15, further comprising a redistribution layer coupled to the first side of the semiconductor die.
 18. The semiconductor package of claim 15, wherein the opening corresponds with a pixel array in the semiconductor die.
 19. The semiconductor package of claim 15, further comprising one or more die pads coupled to each of the one or more dams.
 20. The semiconductor package of claim 15, further comprising a plurality of through silicon vias (TSVs), a passivation layer, a solder mask, and two or more bumps. 